Blackburn, who exited Tuesday's game early, was diagnosed with a bruised right wrist, Susan Slusser of the San Francisco Chronicle reports.
Blackburn was forced to exit Tuesday's game against the Orioles early after being struck on the right wrist by a comebacker in the fifth inning. Preliminary tests revealed no structural damage to the injured wrist, so it sounds like Blackburn may not require a trip to the DL. His availability for his upcoming start will depend on how quickly the bruise heals.